Value of the energy performance certificates in the housing market - what is the weight as evidence of open data?

More and more computable data related to real estate has been opened in Finland in recent years. One of the most interesting services is http://asuntojen.hintatiedot.fi/ which is operated by The Housing Finance and Development Centre of Finland (ARA). Data in the service is about single transactions in the Finnish housing market. Approximately one third of the data contains the information of the energy efficiency class nowadays as well.In the survey the housing market of Helsinki was studied using data covering the year 2014 transactions. As a research method linear regression analysis and OLS estimation were applied to study how the information of the energy performance certificates EPCs was capitalized into transaction values._Results show that there are difficulties to estimate shadow prices for each separate EPC class. But grouping the certificates into bigger entities gave somewhat expected and rational results.Research discuss slightly also the data needed in this kind of estimations. In practical level the transaction based data was enriched by demographic and socio-economic open data to get reliable shadow prices and unbiased results.What is interesting to see is that even though energy efficiency is a factor having a price influence, it is not a search criterion in the biggest Finnish internet housing brokerage services. As a conclusion it can be said that even though EPCs have been part of compulsory information in the real estate market several years, the situation could be almost in its infancy like in the Finnish real estate market which is anyway quite developed market in many ways.